Back into the breach with our weekly Dresden Files game, and because of the lapse in time between sessions/people missing as much as anything else, I had some unique situations occur.

One of the ones I didn't know exactly how to handle was the search for unrelated information; the criminal that they're currently on the trail of is to the large extent a pawn of greater powers, even though he thinks he's the one in control. The research character in the group decided to utilize his extensive library left behind by the warden to try to cross-reference the criminal with supernatural occurrences- but I didn't really have any such relationships established. He wasn't spending FATE points or anything, but he was wanting to make the research roll. He made a pretty exceptional roll, but it seemed pretty cheap to use the roll to say "You didn't find anything." He also wasn't declaring anything to find- he was basically questing for information cold, so I just flew by the seat of my pants with a difficulty and him finding something out tangential to his investigation- but also that there was no relationship to the supernatural with this particular criminal that had been documented.

My question is, in a story-based game like The Dresden Files, if a player fishes for information in a direction that goes off the story line, how do you handle it if he/she is not giving a specific indication of the information to be found/direction to take the story?

For players who don't commit to soe information before rolling, and are asking in directions which don't follow the current story arc from the GM's view, I can see a few directions to go in handling it.

Tell them to make it up before rolling.

Tell them they didn't find anything relevant, but found this other interesting passage (which includes the GM's chosen hooks). If they get overflow, reduce the time and or plant more GM hooks.

Overflow²: they find the nothing on the difficulty, so you let them use the excess on something else.

Method 1 is the simplest... No direction, no statement of what the character already believes, no roll. This ensures that players do not go on "fishing expeditions."

Method 2 is the smoothest, if used in moderation. Some players, however, may be very frustrated by being redirected that way.

Method 3 is less smooth, but means that the next roll has a bonus. The bonus on the following roll may or may not make story sense, but it certainly makes game sense. I would advise caution, however, as some players may see this as grounds to abuse your largesse, and fish for that bonus; those who do have missed the point of the FATE engine, but that is not as uncommon as one might wish for.

Method 4 is simple, but requires that they have something else to do with that surplus.

¹: If used. Spin is an option under DFRPG. See p.214 of Your Story. A defense roll made by 3 levels over needed generates a +1 on the next action. Spin isn't limited to defenses in other FATE games, so it could be applied equally well to other "No benefit from rolling high"
²: There is also Overflow in DF, and that's stock.. pp.214-15 of Your Story

It won't help for the roll already made but you can also bump the time that it would take to find out to something that makes it nit worthwhile to discover. When you tell them it's gong to be difficulty [high value] and take [few days/couple weeks]; You're effectively admitting whatever it turns up will be either crazy high difficulty to get enough extra shifts to knock the tme down to something quick, or potentially interesting in a future game session, but should probably try to focus your efforts on more pressing issues.

You now have a new one! Go with it, add something new and interesting to your city/world. Add something utterly new to the mix -- sometimes, it's best to say "I'll give you information you find next session" if time permits. Otherwise, make something up. You can always justify it later as either a hidden part of your main plot or as a new plot line for the next case file.

Maybe he has just discovered a link between organise crime and the supernatural (kinda Marcone in Chicago) or between an area of town and supernatural crime, or a "violent crimes" path way across the city building into a lay line, or ... You get the idea. You could even ask the player what he expected to find and go with that. Or modify the latter into something that does fit into your plot.